To solve the problems with the measuring of the verticality of oil well pump liners, a simple measuring meter is designed.
英
美
为解决抽油泵衬套垂直度测量较困难的问题,根据抽油泵衬套的特点,设计了抽油泵衬套垂直度简易测量仪。
目录
查词历史
英 汉